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beginner
Problem 01 • Step 02
Pebbles and glasses
On the right is a set of glasses. They stay where they are, so look at them as long as you like. On the left, pebbles flash for a moment.
Then decide: is there a glass for every pebble? After you answer, one pebble drops into each glass so you can see. There are 12 rounds.
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Exercise 02Loading...